Grease an 8"x8"x2" baking pan; set aside.
In a medium saucepan melt margarine or butter and chocolate
over low heat, stirring constantly. Remove from heat. Cool 5 minutes.
Add the sugar, eggs, thawed orange juice concentrate, orange peel, and vanilla.
Beat by hand just until combined.
Stir in flour, nuts, and baking soda until combined.
Spread the batter in prepared baking pan.
Bake in a 350° oven for 20 minutes for a fudgy brownie.
For a firmer brownie, bake 25 minutes. Cool in pan on a wire rack.
Spread Orange-Fudge Frosting over cooled brownies.
If desired, score frosting decoratively with tines of fork.
Cut into bars. Makes 16 brownies.

ORANGE-FUDGE FROSTING:
In a medium mixing bowl stir together 1-1/2 cups sifted powdered sugar
and 3 tablespoons unsweetened cocoa powder.
Add 3 tbs. softened butter, 1 tbs. frozen orange juice concentrate, thawed,
1 tbs. boiling water, and 1/2 tsp. vanilla.
Beat with an electric mixer on low speed until combined.
Beat on medium speed for 1 minute more.
Stir in 1/2 tsp. finely shredded orange peel.